Circulating heater



March 18, 1969 A. .1. HOFMEYER CIRCULATING HEATER Filed May 9, 1966 H7ORA/f) United States Patent 3,433,212 CIRCULATING HEATER Alloyd J.Hofmeyer, Sanborn, Iowa 51248 Filed May 9, 1966, Ser. No. 548,748 US.Cl. 126110 3 Claims Int. Cl. F24h 3/02, 3/00 ABSTRACT OF THE DISCLOSUREA heater having a convolute flue comprising the heat exchanger. Aninsulating housing encloses the flue which lies substantiallyhorizontally. A fan beneath the flue blows air over the flue and outwardthrough ducted openings in the housing.

My invention relates to a circulating heater.

An object of any invention is to provide a heater unit in which a largeproportion of the heat will be saved and transferred to the necessaryspaces without said heat passing through the flue pipe or chimney.

A further object of my invention is to provide a completely fireproofarrangement.

A further object of my invention is to provide a flue pipe which isefficiently cooled.

A further object of my invention is to provide a circulating heaterwhich is eflicient in operation and which includes adjustable featuresfor relieving the vacuum within the unit.

With these and other objects in view, my invention consists in theconstruction, arrangement, and combination of the various parts of mydevice, whereby the objects contemplated are attained, as hereinaftermore fully set forth, pointed out in my claims, and illustrated in theaccompanying drawings, in which:

FIGURE 1 is a sectional view of the circulating heater takensubstantially along the line 11 of FIGURE 2,

FIGURE 2 is a sectional view of FIGURE 1 taken substantially along theline 22 thereof,

FIGURE 3 is an enlarged detail,

FIGURE 4 is a plan view of a modification,

FIGURE 5 is a sectional view taken substantially along the line 5-5 ofFIGURE 2, and

FIGURE 6 is a sectional view taken along the line 6-6 of FIGURE 4.

My invention contemplates the provision of a circulating heater such asan oil burning type which will eliminate the various hazards occasionedby various heaters by being practically completely proof against firedamage and the like, and which will also insure that the minimum amountof heat passes outwardly through the flue pipe, and that the maximumamount of heat is recovered for use.

In describing my invention, I have used the character 10 to designate anupper insulated wall, the characters 11 and 12 indicating furtherinsulated side walls, the characters 13 and 14 indicating furtherinsulated walls, these walls being suitably insulated by means of theinsulation "15 positioned between the metal sheaths 16.

Communicating through the various insulated walls are the variouscylindrical tubes 17 to which any pipes etc. can be attached.

The character 18 indicates a bottom wall having the circular opening at19 and attached as at 20 thereto are the various studs 21 which supportthe framework 22 which are attached to the centrally positioned plate 23upon which is secured an electric motor 24 which drives the fan blades25, such blades being substantially within the opening 19.

The character 26 indicates suitable legs upon which the unit can besupported, or the unit can be suitably sus- 3,433,212 Patented Mar. 18,1969 pended from a ceiling or the like. The character 27 indicates anoil burner of the usual construction having the cylindrical tube portion28 through which the fire Wlll pass and this tube 28 is secured within acylindrical hollow pipe 29 which merges into the further integral pipeportions 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, and 41. The portion41 communicates directly to the vertically positioned flue pipe 42 whichextends through the upper wall 10.

It should be specifically noted that all of the various pipe portionsprovide a continuous passageway whlch is arranged somewhat in a spiralfashion or in other words gradually reduces in size until beingconnected to the flue pipe it being understood that although these pipesare substantially square in plan view, nevertheless they could beoblong, oval or round as desired. An air space 43 is provided betweenthe various portions of the passageways and the outer walls.

Spaced from the flue pipe 42, is a further cylindrical verticallypositioned tube 44, and positioned between the pipes 42 and the tube 44are the helically arranged bafiles or conveyor members 45, there beingthree of the same, and each bafile unit being pitched so as to providethree diflerent passageways, and attached across the upper end of thetube 44 is the further top wall 46. The character 47 indicates openingsin the top wall 46 at the top of the tube 44.

The various helical members terminate at 47 (see FIG- URE 5) andcommunicating at 48 to each of the helical passageways are the tubes 49which extend downwardly, these tubes having the open ends 50 justadjacent to the fan blades 25.

Communicating with the passageway 33 at 51 is a tube 52 whichcommunicates at 53 to the passageway 29, and positioned within this tubeis the disc shaped valve 54 which is attached to the rod 55 to which isattached the handle portion 56 for rotating the valve 54 to the angledesired, the handle portion 56 being located beneath the wall 18.

A modified form of construction is shown in FIGURES 4 and 6 whichconstruction can be used as desired, and the purpose of which will beexplained later. In this construction the pipe 29 will include arectangular opening 57, the character 58 indicating an arcuate memberadapted to uncover or cover the opening 57, the member 58 being heldbetween the round bars 59 which are attached to the pipe 29, andattached at 60 to the member 58 is the rod 61 which passes through thewall 14 and terminates in the knob 62 whereby the closure member 58 canbe regulated as desired.

In describing how my invention operates, it will be noted that the oilburner flame and heat emitted through the member 28 will pass in thedirection of the arrows 63 completely around through the various pipesuntil it reaches the flue 42, where any unburned gases will be emitted,and due to this complete spiral passage of the heat thus generated, theheat will be generated in a relatively flat plane. Meanwhile, the fan24, 25 will be drawing the outside air through the opening 19, which airwill circulate completely around the various pipes above described, andthis warm air will be emitted outwardly through the pipes 17 to thelocation desired by means of pipes, or directly when the pipes are notused.

Due to the insulating features, the heater is constantly protected fromfire damage and the like.

The spacing between the various passageways provides for more completecirculation of the air which is to be heated to thereby considerablyincrease the efliciency of the unit.

In order to prevent turbulence at the end of the burner 28, it isdesirable to inject additional air or gases into the pipe 29 behind theend of the burner. This prevents the combustion gases from blowing backinto that space. Furthermore, and perhaps more importantly, with mypreferred embodiment, a more complete combustion can be obtained byrecirculating the gases over the combustion chamber from the tube 33.Therefore, the tube 52 provides an important function in permitting thisaction. The butterfly valve or flap 54 is controllable to provide theproper amount of recirculation. In the embodiment of FIGURES 4 and 6,the valve 58 provides a similar function except that instead ofproviding for re-circulation, it provides for the injection of fresh aircarrying added oxygen for better combustion.

In some instances when desired the motor 24 can be reversible to providesimilar eflects in a reverse direction.

The tubes 49 will draw the air directly from the fan 25, which colderair will then pass quickly upwardly into the helically arranged baffles45 whereby these three streams of colder air in passing about the fluepipe 42 will efliciently cool down the flue pipe to a considerabledegree to thereby increase the safety features of the unit.

It will now be noted that I have provided the advantages mentioned inthe objects of my invention with further advantages being apparent.

I claim as my invention:

1. A circulating heater comprising an insulated enclosure, a spiralpassageway having an inner terminal centrally of said enclosure and anouter terminal near the outer wall of said enclosure, flue meansconnected to and in open communication with said inner terminal, burnermeans in said outer terminal, means for directing the flow of air oversaid passageway and thence out- Wardly of said enclosure whereby heatexchange takes place between the gas inside said passageway and the airwithin said enclosure but outside of said passageway, and tube meansextending between convolutions of said passageway, one end of said tubebeing adapted to discharge in the region of said burner wherebypartially burned gases may be led oil and recirculated past said burnerfor more complete combustion.

2. The device of claim 1 in which controllable flap means is pivotallymounted in said tube means for control of the flow of recirculated gas.

3. A circulating heater comprising a heat insulated enclosure, a spiralpassageway mounted within said enclosure and having an inner terminalsubstantially central of said enclosure, a flue pipe communicating withsaid inner terminal, burner means within said passageway adapted tocause heated gas to flow therethrough, tube means surrounding said fluepipe, spiral fin means between said tube means and said flue pipeforming spiral duct ways therebetween, fan means fixed to said enclosureadapted to move air through the enclosure and across said spiralpassageway and cooling tubes mounted adjacent said fan and terminatingat said spiral duct ways whereby cooling air is picked up from said fanand conducted directly to said duct ways for better cooling of said fluepipe.

References Cited UNITED STATES PATENTS 1,357,598 11/1920 Thompson126-116 2,811,151 10/1957 Ezdebski 126-116 2,289,759 7/1942 Denise126-110 2,488,548 11/ 1949 MacCracken 126-110 2,619,022 11/ 1952Hergenrother.

2,843,108 7/1958 Campbell et al. 126-110 3,274,991 9/1966 Schmieler126-110 3,306,334 2/1967 Goubsky 158-4 JAMES W. WESTHAVER, PrimaryExaminer.

US. Cl. X.R. 126-116

